The main aim of this case was to remember that the coagulation screen alone is not suitable for ruling out a bleeding disorder. The most common inherited bleeding disorder frequently will have a normal clotting screens. Indiscriminate clotting screens are not appropriate without prior knowledge of the bleeding history. This is especially true in pre-operative assessment clinics, where they may falsy reassure the clinician that there is no bleeding risk. Likewise they may cause alarm/delay/needing further/increased cost when results are abnormal, when after further investigations results are subsequently normal or a factor XII deficiency or lupus anticoagulant is found (no increased bleeding with these).

Von Willebrand disease is diagnosed using a number of tests. The main two are von Willebrand antigen (looking at the amount) and von Willebrand ristocetin cofactor and/or collagen binding (looking at function). Von Willebrand disease is classified as:

Type I – reduction in amount of vWF

Type II – problem with function of vWF +/- amount

Type III – near/complete absence of vWF

Our patient had type I vWD as the vWF-RicoF:vWF-Ag was >0.6

vWD is treated with a combination of:

Tranexamic acid

DDAVP – patients should usually have a diagnostic DDAVP challenge prior to use (often only works well in type I and may not give sustained therapeutic levels)

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